Field of the Invention
The present invention relates to an improved method of and machine for manufacturing U-wall type construction elements for building soil retaining walls and the like, and a method of operating the same with improved levels of efficiency.
Brief Description of Related Art
Retaining walls are widely used in a variety of architectural and site development applications including, for example, office developments, commercial complexes, industrial sites, residential developments, waterfront and coastal structures, and highway cut and fill areas. In such applications, it is not uncommon for the height of retaining walls to exceed 20 feet or more. In nearly all applications, such retaining walls must provide stability against pressures exerted by back fill soil and heavy surcharge loads, and thus be self-supporting.
Self-supporting retaining wall systems are well known.
One popular construction block for self-supporting retaining wall systems is disclosed in U.S. Pat. No. 4,592,678 to McNinch, Jr., et al., which comprises a horizontal cross-section defining a double “T” shape, where the top of the double “T” defines vertical face member and the stem of each “T” defines a generally planar leg member. Notably, elongated tension/reinforcing rods passing through vertically extending holes formed in each leg member are required in order to (i) prevent each stacked block from moving relevant to one another, (ii) achieve vertical alignment of stacked blocks, and (iii) create resistance from overturning moments. While providing a modular construction, such prior art construction blocks and retaining walls, nevertheless suffer from several significant shortcomings and drawbacks.
Another popular construction block for self-supporting retaining wall systems is disclosed in U.S. Pat. No. 5,163,261 to O'Neill, Sr., which comprises a face panel and a plurality of protruding arms. The face panel has a forward wall, a rearward wall, side walls and a top and bottom wall. Such protruding arm extends from the rearward wall of the face panel, and each have an upper wall, lower wall, a back wall and side walls. The upper and lower walls of these protruding arms are each provided with engaging means for facilitating stacking of at least a portion of the protruding arm of one construction element, on top of at least a portion of the protruding arm of another construction element, and preventing relative sliding movement therebetween.
In FIGS. 22 through 24 of U.S. Pat. No. 5,163,261, apparatus is disclosed for molding the U-wall construction elements. As disclosed, the apparatus comprises a face panel mold portion, and a protruding arm mold portion for each protruding arm. The apparatus is typically made from wood or steel panels held together with bolts and nuts, and also includes support means for supporting each protruding arm mold portion substantially vertically upright while the face panel mold portion is cooperatively positioned with respect to the vertically upright protruding arm mold portions. In such a configuration, when concrete or like molding material is poured into the protruding arm mold portions, the concrete fills up the face panel mold portion to a predetermined level. Only after the concrete sets or partially cures in the face panel portion of the block mold, then the protruding arm mold portions can be filled up with concrete.
While the U-wall construction element disclosed in U.S. Pat. No. 5,163,261 has many advantages over the prior art, conventional techniques for manufacturing this U-wall construction block suffer from a number of significant shortcomings and drawbacks.
Conventional methods of U-wall block manufacture require the use of different molds for different sized or dimensioned construction blocks.
Conventional methods of U-wall block manufacture requires a specific sequence of concrete pouring and curing operations during block molding processes, requiring longer times for concrete block manufacture.
Conventional methods of U-wall block manufacture require different molds to provide different textures to the U-wall construction blocks.
Conventional methods of U-wall block manufacture require large amounts of manual labor which is expensive and requires costly human management.
Conventional methods of U-wall block manufacture also creates unnecessary risks to workers required to handle the molds and forms used during prior art constructing procedures.
Thus, there is clearly a great need in the construction art to provide a new and improved way of and means for manufacturing U-wall construction elements while avoiding the shortcomings and drawbacks of prior art methodologies and apparatus.